The People's Perspective on Medicine

Blood Clots, Travel and Deep Vein Thrombosis (DVT)

Did you travel over the holidays? Sitting in a car or plane can increase the risk for deep verin thrombosis (DVT). Such blood clots can show up weeks later.

The holidays are over. Christmas and New Year’s celebrations are in the rearview mirror. We trust you have recovered from all the food and drink. The extra pounds will hopefully disappear after your routine returns to normal. Although all may seem fine, beware an unwelcome leftover from holiday travel. Hours of sitting in a plane, bus or car can lead to blood clots in the large veins of the legs. A deep vein thrombosis (DVT) can sneak up on you after returning home. Clots can arise days or even weeks after travel.

What is Deep Vein Thrombosis (DVT)?

When you sit or remain inactive for many hours, blood flow in leg veins may slow down. It’s not just air travel that is risky. We know people who hate to stop on the Interstate. They drive for 6 to 8 hours without a pitstop. That may be just as dangerous as sitting in a cramped airplane seat while flying across the ocean. Even a long bus trip could put you at increased risk for a DVT.

Thrombosis means the development of a clot in a blood vessel such as a vein or artery. The clot itself is called a thrombus. Medicalese often originates from Greek and Latin. The Greek word thrombos loosely translates to clump.

When a clump of blood cells gang together in a vein deep in the legs or thighs you’ve got a deep vein thrombosis (DVT). When the clot restricts blood flow through a vein it is called venous thromboembolism (VTE). If part of the thrombus breaks loose and travels to the lungs it is a pulmonary embolism (PE). Wherever the clot lodges, it can spell trouble.

How Common is Deep Vein Thrombosis (DVT)?

We suspect that most health professionals think that DVTs and PEs are relatively rare. They would be wrong. Life threatening DVTs are more common than some of our most common health conditions. More about that in a moment. In truth, good statistics about venous thromboembolisms are hard to come by. The CDC admits as much. Here is the overview from this highly regarded public health institution:

“• The precise number of people affected by DVT/PE is unknown, although as many as 900,000 people could be affected (1 to 2 per 1,000) each year in the United States.
• Estimates suggest that 60,000-100,000 Americans die of DVT/PE (also called venous thromboembolism).

  • 10 to 30% of people will die within one month of diagnosis.
  • Sudden death is the first symptom in about one-quarter (25%) of people who have a PE.

• Among people who have had a DVT, one-half will have long-term complications (post-thrombotic syndrome) such as swelling, pain, discoloration, and scaling in the affected limb.
• One-third (about 33%) of people with DVT/PE will have a recurrence within 10 years.”

Deaths from DVT:

We have searched the medical literature to try and verify the number of people who die annually from a venous thromboembolism (VTE). We were shocked to read this acknowledgement from leading authorities (American Journal of Preventive Medicine, April, 2010)

“Presently, there is no national surveillance of VTE, and current prevalence and incidence estimates are likely underestimates…Further, PE often presents as sudden death. Given that the number of autopsies performed in the U.S. is low, and that PE may be misdiagnosed as heart failure, current estimates of the number of PE events are probably low.”

We have searched the medical literature for more information on missed diagnoses and DVT. You can read about our research in our book, Top ScrewupsWe suspect that annual mortality rates for VTE may be substantially higher than CDC estimates. That’s based on stats from experts at the Cleveland Clinic.  They state that:

“• Approximately 300,000 US citizens have a fatal PE each year (mortality exceeds that of breast cancer, HIV and motor vehicle accidents combined)

• PE is the most common preventable cause of hospital death (responsible for 10% to 15% of all in-hospital deaths)

Source: 2009 AHA Heart Disease and Stroke Statistics
2008; 358: 1037-1052″

STOP! Go back and reread what is in the parenthesis above. Did you know that mortality from pulmonary embolism “exceeds that of breast cancer, HIV and motor vehicle accidents combined”? We didn’t think so. We too were shocked. This is serious stuff!

Symptoms of Deep Vein Thrombosis (DVT):

When blood clots break loose from veins and migrate to the lungs, the result can be life threatening. Sudden death might be the first symptom of PE. Up to one third of those diagnosed with DVT/PE die within a month of being diagnosed.

That is why it is so important to recognize the symptoms of a possible blood clot as early as possible. Swelling, redness, tenderness and pain in one leg can be an early tip-off.

If the clot lodges in the lungs (PE), it can cause chest pain, shortness of breath, rapid breathing, trouble breathing, chest pain after deep breaths, irregular heart rhythms, lightheadedness, low blood pressure or coughing up blood. Do NOT delay. Sudden death can be a consequence of a pulmonary embolism!

DVT/PE A Leading Diagnostic Mistake

It can be challenging to uncover the most common diagnostic errors made by health professionals. No one likes to admit making a mistake. But if doctors are given the opportunity to discuss this issue anonymously, they often reveal some interesting information.

A survey of 310 internists, specialists and emergency physicians conducted at 22 institutions revealed that the most frequently missed diagnosis was pulmonary embolism or PE (Archives of Internal Medicine, Nov. 9, 2009).

We discovered that diagnostic mistakes involving pulmonary embolism were also a major cause of malpractice claims. That is why it is so important for patients and families to be vigilant when it comes to symptoms of deep vein thrombosis (DVT) or pulmonary embolism (PE).

Preventing DVTs and PEs:

People who are immobile for a long time are more susceptible to DVT. One reader wrote about this experience:

“I took a long car trip (over 20 hours), only stopping for gas. I developed DVT in my leg and am now on blood thinners, apparently for life. Was the trip partly the cause?”

While traveling can sometimes be responsible for clot formation, lying still in a hospital bed is also a risk. Another reader related:

“I had bilateral knee surgery and developed a clot (DVT). As a result, I now take Xarelto. This drug made me short of breath and gave me muscle fatigue after even the slightest activity. The doctors insisted it wasn’t the drug, but when I was able to discontinue it, I felt much better.”

Knee or hip replacement surgery pose serious risks for blood clots. It is essential that patients discuss preventive strategies BEFORE undergoing surgery. Here is a link to an article about this very topic:

Many health professionals are surprised to learn how effective aspirin can be at preventing blood clots after joint replacement surgery (Bone Joint Journal, Nov. 2017). Again, medical supervision is essential!

Treating Deep Vein Thrombosis (DVT):

When a person is diagnosed with a blood clot in a deep vein in the thigh, the treatment is usually anticoagulant medication. Heparin is a common anticoagulant that is used in hospitals. Although drugs such as apixaban (Eliquis), rivaroxaban (Xarelto) or warfarin (Coumadin) don’t dissolve such clots, they keep others from forming.

Another treatment that appears helpful to prevent complications is compression therapy (Blood, Nov. 22, 2018). Special elastic hosiery that squeezes the legs has been shown to help reduce some of the adverse effects of a DVT.

Preventing Blood Clots During Hospitalization:

After surgery, patients often have reduced mobility for several days. This can increase the risk for blood clot formation. If a patient has to lie in a hospital bed without moving, doctors sometimes order intermittent pneumatic compression (IPC). These flexible sleeves fit around a patient’s legs. They periodically fill with air, squeeze the legs and improve blood flow through veins.

There is even a portable leg wrap (CIRCUL8) from Precision Medical Products. It can be operated through an app on a cell phone. The rhythmic compression while riding on an airplane or in a car can help reduce the risk of clots. You may need to ask your doctor for a prescription and check to make sure your insurance company will pay for this device. We suspect it is pricey. Those at risk, however, should be covered.

For those who are especially susceptible to blood clots, low-dose aspirin may also be beneficial. A study of people who were at high risk of developing a recurrent DVT or PE reported that low-dose aspirin could be protective (European Journal of Internal Medicine, Jan. 2014). Do not try this without medical supervision!

Aspirin vs. Xarelto (Rivaroxaban)

We were astonished to learn that aspirin was as good as the far more expensive drug Xarelto when it came to preventing blood clots after knee or hip replacement surgery. If you would like to read more about this intriguing study, here is a link.

Travel Smart!

Even people who have never had a deep vein thrombosis (DVT) may benefit from precautions when traveling. Standing up and walking around every hour or so gets the blood flowing. If you are especially susceptible to blood clots ask your physician whether you need to take prophylactic medicine before traveling.

Moving your legs or wearing compression hose on a long trip could help holiday travelers get home safely. We suggest consulting a health professional about the right kind. Such stockings are measured by the pressure they exert: mm (millimeters) of Hg (mercury). It is recommended that people who are vulnerable wear 15 to 30 mm below-the-knee compression stockings if they have to travel for many hours. Not everyone should wear elastic stockings, however. Support hose that is too tight may cause vein thrombosis or cut off blood flow in susceptible individuals.

The experts at the Cleveland Clinic recommend that long-distance air travelers:

“exercise the legs by flexing and extending the ankles at regular intervals. Walk about the cabin periodically, 5 minutes for every hour on longer duration flights (> 4 hours). Drink adequate amounts of water and fruit juices.”

Share Your Own Experience!

Have you ever had a blood clot? Please share your story with other readers in the comment section below. We fear that most people do not appreciate the significance of a deep vein thrombosis (DVT) or pulmonary embolism (PE). Prevention is always the best medicine.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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I was diagnosed with a deepen thrombosis that went from my pelvis and down my entire leg. I also had PE. I was in the ICU for 5 days. I had no previous warning. It hit me suddenly when I couldn’t stand, and my leg up to my hip turned purple and was swollen. I was 49 with no major health issues or family history of blood clots. I had not traveled in quite a while. The only thing we can figure is it happened because my doctor put me on birth control pills for endometriosis. I’m currently taking Eliquis. When I finish my Eliquis treatment, I will have to have the hysterectomy the doctor was trying to avoid by my taking hormones.

Three years ago my 80 year old sister fainted and was taken to the ER. Except for being a little short of breath, she told the staff she had no pain or other symptoms after xrays and other tests, she was sent home. A week later, she fainted again. This time she was taken to a different ER. She was diagnosed with multiple pulmonary embolisms, was put on warfarin and sent to the icu for several days. Eventually she began long term rehab which was very arduous and she’s never regained her mobility. Heaviness in her legs makes walking very difficult and only achieved with a walker. Had she been diagnosed and properly treated, would she be more vital and mobile? I think so.

The enzyme nattokinase (taken between meals) can be very effective at preventing clot formation. People on certain medications should not take it.

Joe and Terry, please interview an enzyme specialist on your fabulous radio show! Enzymes provide some great therapies that can sometimes help people avoid serious health problems and/or pharmaceutical drugs.

My brother Matthew died suddenly from pulmonary emboli (multiple embolisms in the lungs) in 2012 at the age of 54. We know because we did have an autopsy done. He lived alone so we don’t know if he had symptoms in a leg. He had become sedentary because of hip pain, and was contemplating hip replacement surgery. I, myself, had the d-dopler test done, and it showed normal blood clotting factor. Exercise regularly and don’t sit for more than a couple hours at a time.

My husband has had a problem with DVT’s since he was 21 and was the victim of a medical mistake. In 2012 he got a DVT after sitting in a cramped theater seat for several hours without being able to put his leg out. He was hospitalized for a week, given Lovenox shots in the abdomen and put on Warfarin. He stayed on the Warfarin for 10 months until the side effects became unbearable. He had no problems for 6 years.

Two days after standing in line at the Social Security office for 3 hours he began with pain in his leg. He said it felt like his leg was broken when he walked down the stairs. He immediately went on aspirin and called his cardiologist, who sent him for a Venous Doppler. They detected 3 separate DVT’s in his leg.

He was immediately sent to the ER where they drew blood, administered Lovenox, and because his blood work came back OK put him on Xarelto and sent him home. Within a few days the pain was gone. He continued on 20 mg of Xarelto for 6 months and just last week the doctor dropped his dose to 10 mg per day. He will stay on the drug for another 6 months.

I was on a 3 hour bus trip in the Dominican Republic from Santo Domingo to the airport at Punta Cana, to take a return flight to Canada. The seats are very close together on those buses, and I couldn’t stretch my legs out in front of me. I was in a window seat so I couldn’t stretch my legs out in to the aisle either.

I boarded the flight, and noticed a dull ache in my left leg, but didn’t think it was anything to worry about. Upon driving home from the airport in Toronto after a 4 hour flight I experienced a dull ache in my left leg, almost enough discomfort to make me pull over and try to walk it off. It finally eased off before I arrived home after the 45 minute drive.

The next morning I woke up with a pain in my upper left lung, similar to the pain I experienced with pleurisy years earlier. It was very bothersome so I went to see my doctor forthwith. He ordered an x-ray and a blood test, which were done in the same building. Shortly thereafter he ordered me to go directly to the Emergency department at the hospital nearby. He said I had experienced a pulmonary embolism.

When I arrived at the hospital I was immediately given a CT scan. When the scan was completed, the doctor on duty told me that I had many blood clots in my lung, too many to count! He said a large clot had entered my lungs, broken up into many smaller clots, and that it was fortunate that I was still alive.

I was admitted to the hospital and spent three days there, having injections of blood thinner and medications. I was released from the hospital and had to take warfarin for six months, as well as a few more injections. I was sent to the Thrombosis center in Toronto where there were more tests done, including a DNA test to see if there was any genetic cause for the PE. That came out negative.

The Thrombosis specialist told me that I was not prone to clots or embolisms, but that I should never sit on a bus or airplane again for any length of time without stretching out my legs. Lesson learned!! Now when I fly I wear compression stockings up to my knees and I avoid cramped buses.

I had PEs in both lungs without precipitating DVT a few years ago. My only symptoms were a very rapid heart beat followed by sweating. As a 62 year old woman, I thought I might be having atypical symptoms of a heart attack, which is why I went to the Emergency Department. I had no DVT proceeding my PEs. Doctors have called my PEs “idieopathic,” that is, they don’t know what caused them. I have no blood factors that would predispose me to this condition. So, if you have symptoms that are unusual for you, get it checked!

Thank you for covering this topic which is too little recognized by both the general public and even doctors. In addition to other modalities, Nattozyme is highly effective in keeping clots from forming, or dissolving them when they do. It does this by keeping excess fibrin in check.

I had a DVT about 40 year ago. I was in hospital for 1 week with Heparin lock, out for a week back in for a week. I was about 45. Last January 2018 I had PE and in 2 ER’s and hospital for 3 days taking Lovenox shots. Now on Eloquis twice a day for past year. I am 83. Glad to be alive.

We always take a baby aspirin before a long car trip (64 and 68). Are we doing the right thing? There is a history of this problem in my family.

Wow, I didn’t know DVT was so prevalent. I’m 88 yrs old and I traveled 6 hours by air from Tampa, FL to San Francisco, CA the day before Thanksgiving to celebrate the holiday with family. Then another flight San Fran to San Diego a few days later to help my daughter with her move. After the movers picked up her household effects on 12/9, we drove from San Diego (West to East) to Arlington, VA where her new job is located. It took us 5 days, driving approx 9 hours a day. I finally returned home to Tampa (Seminole) FL on 12/28, a 2.5 hr. flight. So far, thank God, I am not aware of any problems but I will be seeing my PRimary Care doctor this week.

I started to get DVTs and pulmonary emboli when I was about 45. When I moved to Florida in 2001, I was hospitalized with a DVT. My primary care physician had a blood specialist visit me. It was a big surprise to me to learn I had a genetic blood disorder – Factor V Leiden. I am now on Coumadin and will be for the rest of my life. When I was first correctly diagnosed, DNA testing wasn’t available. Thanks to my very intelligent primary care doctor I now know what the problem is. I’ve had no clots anywhere since then.

After hip replacement surgery in October, 2018, I went into cardiac arrest which took several minutes for me to start breathing. I was hospitalized for 8 days. Over two months later I still have redness, tenderness, and swelling in my foot/ankle/leg. I had many tests including an echocardiogram, ultrasound, and lexiscam yet no one has a diagnosis or knows why my heart stopped. I have had no previous health problems, not overweight, and went to the gym regularly and am 74 y/o. I go to PT. I find this very scary not knowing what caused this and why I have ongoing issues or what to expect.

For vacation we drove for 5/6 hours for 2 days to reach upper Canada stopping only for gas every other day. Once there we walked for a mile or so/ day, but on the third day one of my legs swelled to inflexibility and I couldn’t think of a cause. The pain continued for 2 weeks with relief occurring only when we thought of a DVT as the cause and started 2 aspirin/ day. Have backed to one a day prophylactically with no more problems since.
I’d love to find a method to check our own clotting factors as we find our susceptibility to clots increases.

One good class action against airlines would solve the lack of inhabitable space on airplanes.

I had an operation at a leading Baltimore hospital in 1995. After a week-long stay, I was released to return home to Florida, about a two-hour flight. Almost one week after returning home, I was showering when I blacked out and collapsed. My wife found me and rushed me to the hospital where my primary care doctor and E.R. staff diagnosed my issue as a DVT in my right leg, just below the knee.

The primary treatment was Coumadin which I was on for several weeks following discharge from the hospital. A visiting nurse came to my home several times per week to check my blood pressure and remind me to stay away from certain foods which would reduce the effectiveness of Coumadin.

Twenty-three years later I have some swelling in my lower right leg and have no hair growth there. I am very lucky to have no additional complications and no further issues. At the time of my blackout, I remember my doctor being largely concerned that the blood clot (DVT) might travel to my lungs which might have been fatal! I have avoided long plane trips and am careful to walk every two hours on long auto rides.

I was diagnosed with DVT when I was 20. I am now 70, proving that you can live a long, normal life with DVT. I take warfarin daily, wear 30-40 mm thigh high compression stockings, and have an INR bood test every 4 weeks.

My doctor periodically has to readjust my warfarin dosage to keep me in the correct range. I need to avoid alcohol and any foods which contain large amounts of Vitamin K since these will interfere with the warfarin. I take a brisk walk every morning to maintain my circulation. I need to avoid situations where I am standing without moving or sitting in a cramped position. At home, I sit with my legs elevated.

I had the symptoms mentioned above ” Swelling, redness, tenderness and pain in one leg can be an early tip-off.” and went to the doctor. A general exam of my knee led me to a surgeon who had X-rays taken and and MRI of my knee. It was apparently not a blood clot but a torn meniscus. It has been gradually healing itself over 6 months. You did not mention where the swelling redness, etc. would be located in one leg…..thigh, calf, or knee? Thanks for your columns.

I read that long term untreated chronic pain will increase the chances of DVT. I was wondering if there is any truth to this.
Actually, if you would be willing to address this, I know many people who would like an unbiased answer about any harm done to a person’s health as a result of untreated chronic pain.

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